The concentration of hepatocyte growth factor (HGF) in human amniotic fluid at second trimester: relation to fetal birth weight.

Hepatocyte growth factor (HGF) was measured in 28 samples of amniotic fluid, 1 of fetal urine and 5 of first neonatal urine. The mean level of HGF was 12.4 +/- 4.5 ng/ml (second trimester) and 10.5 +/- 6.6 ng/ml (third trimester). These values were extremely high compared to that in plasma from normal subjects and greater than the plasma levels from patients with acute hepatitis. The concentration of amniotic HGF at second trimester showed a significant inverse correlation both with birth weight (r = 0.47; p < 0.05) and birth weight deviation (r = 0.54; p < 0.02). The level of HGF in fetal urine (0.10 ng/ml) and in the first neonatal urine (0.08 +/- 0.02 ng/ml) were much less than that in amniotic fluid. HGF stimulated DNA synthesis of human fetal liver cells in vitro. While the effect was dose dependent, a maximal response was reached with about 0.2 ng/ml, attaining a 1.3-fold stimulation. The presence of extremely high levels of HGF in the amniotic fluid may be involved not in fetal growth, but rather in maturation of fetal organs such as the lung and the digestive tract.